The ability to reliably detect and characterise defects embedded in austenitic steel welds depends on prior knowledge of microstructural descriptors, such as the orientations weld’s locally anisotropic grain structure. These are usually unknown but it has been shown recently that they can be estimated from ultrasonic scattered wave data. However, conventional algorithms used for solving this in...

This paper describes the development and evaluation of neural network-based systems for industrial welding process control and weld quality assessment. The developed systems utilize recurrent neural networks for process control and both recurrent networks and static networks for quality prediction. The first section describes a system capable of both welding process control and real-time weld q...

Presently, wrapping of the welds at the ends of stiffeners is not done to avoid the undercutting of the stiffener corners and the attendant weld repair. The fatigue performance of stiffeners with undercuts was evaluated in a factorial design fatigue experiment. Undercuts at the flange edge and filling of the stiffener cope with the fillet weld were also evaluated. The undercuts did not influenc...

An application of machine vision, incorporating neural networks, which aims to fully automate real-time radiographic inspection in welding processes is described. The current methodology adopted comprises two distinct stages the segmentation of the weld from the background content of the radiographic image, and the segmentation of suspect defect areas inside the weld region itself. In the first...

Numerical simulation can provide quantitative information on ultrasonic beam propagation and plays an important role in analyzing its detection ability optimizing the corresponding parameters of phased array testing (PAUT). In this paper, a fast finite element method PAUT is developed using improved explicit integration algorithm non-zero compressed storage method. The new applied for type-B sl...

Mathematical models and associated numerical techniques have been developed to investigate the complicated transport phenomena in spot hybrid laser-MIG keyhole welding. A continuum formulation is used to handle solid phase, liquid phase, and the mushy zone during the melting and solidification processes. The volume of fluid (VOF) method is employed to handle free surfaces, and the enthalpy meth...

Evaluation of the low cycle fatigue life by the small specimen test technique (SSTT) and some other properties (metallographical structure and Vickers hardness) for the TIG (tungsten inert gas) weld of F82H IEA-heat were carried out. The TIG-weld was distinguished into seven regions with different metallographical structure and hardness, which were the base metal (BM) region (region with almost...

In fusion arc welding the final weld shape is influenced by welding parameters, mode of metal transfer, number of welding wires used and their arrangement in the contact tube, type of material to be welded, type of shielding medium and similar. In some articles, descriptions of investigations on the influence of the kind of material and the type of shielding medium used on the weld shape and si...